Zesty Nimble to JGAurora A5 direct mount

This design is intended to mount a Nimble V1.2 to the original A5 printhead. It is not suitable for the newer Nimble V2.

The design uses a right-handed nimble. It uses the existing bowden coupler to fasten the adapter to the print head. A guide on top covers the bowden coupler and aligns the PTFE tube with the Nimble. Cut the PTFE tube flush with the top of the guide so that the Nimble can clamp it down properly. For more detailed instructions, see the Nimble Basic Adapter

Note: The screenshots do not always show the latest version of the objects.

Things used for visualization:

• JGAurora A5 printhead model
• Mockup of the Zesty Nimble: Lightweight direct drive extruder
• Reverse Bowden Holder

Additional required hardware:

• The Zesty Nimble Remote Direct Extruder
• Nema 17 Bipolar 1.8deg 13Ncm stepper motor

Due to the 1:30 gear ratio of the Nimble, Marlin needs to be reconfigured, compiled and installed on the printer.

Post-Printing

Preparation

Glue one M3 nut in each of the mount plate's recessed hex holes with superglue. Use M3 screws to pull in the nuts and apply sufficient pressure while glueing. Be careful not to glue the screws and nuts together.

The center bore of the nimble guide needs to be a tight fit for the PTFE tube (OD 4mm). check if it needs to be widened before installation.

Installation

Basic installation steps:

• Remove the black cable guide plate
• Install the printed cable guide with two M3x8 cap screws
• Remove the bowden tube and bowden coupler and washer from the printhead
• Install the mounting plate and fasten it with the bowden coupler (leave out the washer)
• Mount the Nimble according to the Zesty Nimble documentation.
• Insert the PTFE tube back into the bowden coupler, make sure to shove it all the way down to meet the heat break
• Cut the PTFE tube about 1cm above the holder - an angled cut will help with the next step
• Install the nimble guide flush with the mount plate. Cut the PTFE tube flush with the nimble guide. See Nimble Basic Adapter for details.
• Proceed installing the Nimble as described in the Zesty Nimble documentation

Firmware configuration

Settings that work with my printer:

• Configuration.h:

#define EXTRUDE_MAXLENGTH 100 
#define DEFAULT_AXIS_STEPS_PER_UNIT { 80, 80, 800, 2660 } 
#define DEFAULT_MAX_ACCELERATION { 1000, 500, 100, 120 } 
#define DEFAULT_RETRACT_ACCELERATION 120 // E acceleration for retracts //#define JUNCTION_DEVIATION 
//#define S_CURVE_ACCELERATION 
#define DEFAULT_EJERK 5 // May be used by Linear Advance

• Configuration_adv.h (if you have installed TMC2208 drivers):

#define E0_CURRENT 400 
//#define STEALTHCHOP_E

In case you have Marlin 2.0.x running on a 32bit controller board and a TMC2208 driver for the extruder, consider activating SQUARE_WAVE_STEPPING in Configuration_adv.h

Further Upgrades

If you need a vinyl cutter you might consider adding a drag-knife to the print-head with the JGAurora A5 E3D drag knife mount [vinyl cutter]: